Table 4.
Association between the levels of global DNA methylation and the clinical variables of patients undergoing pre-treatment for colorectal adenocarcinoma.
| Clinical Variables | Global DNA Methylation in Tumor (%) |
Global DNA Methylation in Blood (%) |
||||
|---|---|---|---|---|---|---|
| n | Mean (SD) | p | n | Mean (SD) | p | |
| Tumor location | 111 | 123 | ||||
| Colon | 83 | 53.12 (±23.55) | 0.35 | 92 | 25.60 (±13.23) | 0.30 |
| Rectum | 28 | 48.16 (±26.18) | 31 | 31.39 (±30.20) | ||
| Clinicopathological staging | 111 | 123 | ||||
| I and II | 58 | 50.15 (±23.49) | 0.43 | 68 | 23.29 (±8.17) | 0.01 * |
| III and IV | 53 | 53.76 (±25.07) | 55 | 31.73 (±26.32) | ||
| Polymorphism C677T | 102 | 123 | ||||
| CC | 43 | 53.77 (±25.21) | 0.84 | 50 | 27.21 (±16.15) | 0.91 |
| CT | 42 | 51.53 (±24.35) | 49 | 27.61 (±24.57) | ||
| TT | 17 | 55.28 (±25.60) | 24 | 25.62 (±9.84) | ||
| Polymorphism A1298C | 102 | 123 | ||||
| AA | 62 | 56.72 (±27.42) | 0.11 | 78 | 27.15 (±20.27) | 0.74 |
| AC | 33 | 49.19 (±19.69) | 37 | 27.92 (±18.26) | ||
| CC | 7 | 39.44 (±11.41) | 8 | 22.19 (±5.34) | ||
| Polymorphism C677T | 102 | 123 | ||||
| CC a | 43 | 53.77 (25.21) | 0.81 | 50 | 27.21 (±16.15) | 0.94 |
| TT + CT b | 59 | 52.61 (24.55) | 73 | 26.96 (±20.84) | ||
| Polymorphism A1298C | 102 | 123 | ||||
| AA a | 62 | 56.72 (27.42) | 0.04 * | 78 | 27.15 (±20.27) | 0.94 |
| CC + AC b | 40 | 47.48 (18.77) | 45 | 26.90 (±16.80) | ||
SD = standard deviation; a wild-type homozygous; b mutated homozygous + heterozygous; * p < 0.05.